Method for providing polymers with durable improved properties

ABSTRACT

Polymers reactive towards free amino groups, such as polyamides, polyureas, polyurethanes or polyesters, are provided with durable modified properties by being brought into contact with an additive polymeric material which (a) is compatible with the polymer being treated, (b) contains a plurality of oxyalkylene groups effective to impart to the modified polymer improved properties such as reduced static propensity, modified dyeability, or greater water absorbency; and (c) has one or more reactive sites, in the form of a pendant free primary amino group or potential primary amino group, blocked by the dehydration of an aldehyde or a ketone with the amine, which in either case affords the capability in proper circumstances of attaching the modifying polymeric material to the polymer being treated by a covalent chemical bond. Suitable modifying polymers are made by reacting a diamino or higher amino compound with a proportion of an aldehyde or ketone sufficient to block at least some of the amino groups present, oxyalkylating the blocked starting material through a surviving amino group to an extent capable of affording the desired properties, and if desired, cross-linking or chain-extending the resulting material to obtain a substance of increased molecular weight. Modifying polymers so made may be used as such (i.e., in the aldehyde- or ketone-blocked form) for treatment of the reactable polymer to be modified, either by blending into a melt or by surface treatment of freshly produced fiber or sheet material. The formation of free amino groups in the modifying polymer can occur in situ when the modified polymer is exposed to water under suitable conditions. The modifying polymer may also be used in a free amino form generated by hydrolyzing before bringing it into contact with the polymer to be modified. Novel treated polymers are thus produced which display modified properties which are retained despite repeated washings and/or long-continued use.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a method for providing polymers with modifiedproperties and in particular to a method for providing improved anddurable anti-static properties to nylon; it relates, moreover, to noveltreated polymeric materials so produced.

2. Description of the Prior Art

It is known in U.S. Pat. No. 3,329,557 to Magat and Tanner to usepolyoxyethylene of high molecular weight to impart static-resistantproperties to nylon filaments. More specifically, it is disclosed inU.S. Pat. No. 3,475,898 to Magat and Sharkey to usepoly(ethylene-propylene) ether glycols for the same purpose. This samepatent discloses that residues of initiating compounds such as diaminesmay be present within the polymer chain. Other patents relating to theproduction of anti-static polyamides or polyesters include Pat. Nos.3,825,619; 3,637,900; 3,794,631; 3,808,291; 3,755,249; 3,755,497; and3,848,023.

In U.S. Pat. No. 3,231,619, it is taught that a polyether containing aprimary amine group may be made by reacting a primary amino alkanol withan aldehyde or ketone to produce a Schiff base, then oxyalkylating, thenhydrolyzing the resulting material to reconstitute the free primaryamino group.

DESCRIPTION OF THE PREFERRED EMBODIMENTS I. Polymers which can bemodified according to the invention

According to the invention, polymers which may be modified are ones thatare reactive with respect to free amino groups. These include thepolyamides such as Nylon 6, and Nylon 6-6, among others, thepolyurethanes, the polyesters such as the polymer produced by thereaction of dimethyl terephthalate or terephthalic acid and ethyleneglycol, and others. It does not include polymers not having in theirstructures any reactive sites at which a material containing one or morefree amino groups may react by amidation or transamidation to form acovalent bond, e.g., polyethylene, polypropylene, SBR, isoprene,polyvinyl alcohol, polystyrene, etc.

II. Manner of Modifying Polymers

According to the invention, polymers capable of reacting with pendantprimary amino groups are modified by being brought into intimate contactunder reactive conditions with the modifying polymer, produced ashereinafter explained. In some instances, this may be done by blending0.5 to 20 weight percent of the modifying polymer in a melt of thepolymer to be treated, prior to the formation of a fiber or film orsheet or the like. In other instances, the modifying polymer, producedas explained below, is applied to a polymeric material after it has beenproduced in an extended form, i.e., has become a fiber, film, sheet orthe like.

In either event, it is intended that the polymer to be modified and themodifying agent be brought into contact under conditions such as willpermit their reaction, by amidation or transamidation or the like, toform a covalent bond between them, thereby affording a treated producthaving permanently altered properties.

III. Characteristics of Modifying Polymers

Modifying polymers have two principal characteristics: a suitableoxyalkylene content arrived at by experimentation with each substrateand a reactive pendant amino group or a precursor of such reactivependant amino group.

The modifying polymer has a suitable oxyalkylene content. In order tobring about desired changes in the polymer to be modified, such asdecreasing its ability to develop and retain a charge of staticelectricity or improving its compatibility with various dyes, it isdesirable to use a modifying polymer of experimentally determinedhydrophilic/hydrophobic balance. Such polymers are obtained byincorporating substantial numbers of oxyalkylene units, usuallyamounting to between 20 and 95 weight percent of the modifying polymer.Such polymers are made by reacting a compound containing at least oneactive hydrogen atom with the suitable number of moles of an oxiranecompound or a mixture of such compounds. Ethylene oxide is usually to bepreferred; it may be used alone or in combination with other loweralkylene oxides such as propylene oxide, butylene oxide, or otherrelated alpha olefin epoxides.

The preferred characteristic i.e., that of containing a pendant reactiveamino group or a specified precursor thereof, is of critical importancebecause such a reactive group affords the means by which the modifyingpolymer may become chemically bonded to the substrate polymer, therebymaking the modification durable, i.e., capable of persisting throughrepeated washings and long-continued use. A modifying polymer accordingto the invention has at least one such reactive pendant amino group orprecursor thereof, and may contain several such groups. As will bediscussed below in greater detail, such reactive groups are obtained bystarting with a diamino compound or a polyamino compound, blocking oneof the free amino groups by reaction with an aldehyde or ketone to forma Schiff base, and then oxyalkylating. If desired, the polymer producedas the result of such oxyalkylation may be hydrolyzed to convert theblocked amino group or groups to free amino groups before the polymer isused as a modifying agent; alternatively, the modifying polymer whilestill in its blocked form may be applied to or mixed with the polymer tobe modified and then, later, converted in situ to the free amino form byhydrolysis and so freed, to react with the polymer to be modified.

IV. Starting Materials

In accordance with the invention, one starts with a material having aprimary amino group and at least a second group that contains an activehydrogen atom and is capable of being oxyalkylated. Preferably, thestarting material is a diamine or polyamine, such as ethylenediamine,diethylenetriamine, triethylenetetramine, polyethyleneimine,1,6-hexamethylenediamine, 2,4-diaminotoluene, 2,6-diaminotoluene, or amixture of 2,4- and 2,6-diaminotoluenes. Also an amine-terminatedprepolymer, such as one made by reacting an excess of a diamine, such as1,6-hexamethylene diamine, with a relatively small proportion of adiacid, such as adipic acid, or other prepolymers formed by an aminesuch as for example diethylene triamine and epichlorohydrin, amongothers, can be employed.

V. Blocking Agents

In the first step of the making of a modified polymer in accordance withthe invention, a starting amino compound as mentioned above is reactedwith an aldehyde or ketone to block at least one of the amino groupspresent in the starting material. In performing this blocking reaction,care must be taken not to block all of the active hydrogen atoms of thestarting material, one or more of which must remain in order that thesubsequent oxyalkylation step may be performed. The aldehyde or ketoneused to perform the blocking reaction is of the formula

    B.sup.1 B.sup.2 C=O

in which B¹ represents a hydrocarbon radical having from one to 12carbon atoms and B² represents hydrogen or a hydrocarbon radical havingone to 12 carbon atoms. Suitable ketones for the reaction includeacetone, methylethyl ketone, methylisobutyl ketone, ethylisobutylketone, diethyl ketone, diisobutyl ketone, and the like. Effectivealdehydes include isobutyraldehyde and 2-ethylhexaldehyde.Beta-substituted aldehydes are preferred, and aldehydes which condensein the presence of a strongly alkaline catalyst to aldol compounds arenot suitable.

VI. Production of Partly Blocked Amines

In most instances, the reaction between the blocking agent and thestarting amino compound takes place readily, particularly at amoderately elevated temperature such as 50° to 175° Centigrade. Ifdesired, an inert solvent may be added to facilitate the removal ofwater liberated by the reaction through formation of an azeotrope. Ifthe starting material is one which will not be deprived of all of itsactive hydrogen atoms by the use of the blocking agent, an excess of theblocking agent may be employed as solvent. For example,diethylenetriamine is capable of retaining an active hydrogen atom inthe presence of an excess of ketone, whereas ethylenediamine is not.

VII. Oxyalkylating Agents

The partly blocked amine made as described above is reacted with analkylene oxide under oxyalkylation conditions to form an oxyalkylatedblocked amine. The alkylene oxide adds onto the partly blocked aminocompound at the location of an active hydrogen atom, which may be anamino or hydroxyl group. A wide range of such compositions may beprepared, ranging from materials of low molecular weight having 10 or 20moles of alkylene oxide per mole of partly blocked amine to compositionsof relatively high molecular weight in which 100 to 200 or more moles ofalkylene oxide have been combined with one mole of partly blocked aminocompound. Other important variations may be obtained by employing morethan one alkylene oxide reactant, either in mixtures or sequentially.

The alkylene oxide compounds which may be employed according to theinvention may be represented by the formula ##STR1## in which Rrepresents hydrogen or a hydrocarbon radical having from one to 20carbon atoms. Suitable alpha olefin oxides include ethylene oxide,propylene oxide, 1,2-butylene oxide and 1,2-octadecane oxide.

Oxyalkylation of the partly blocked amine is desirably conducted at amoderately elevated temperature. Thus, the reaction may be conducted ata temperature in the range from about 40° to about 200° Centigrade withthe preferred operating temperature being from 55° Centigrade to about150° Centigrade. Moderately elevated pressures are preferably employedto improve the concentration and contact between the alkylene oxide andthe partly blocked amino compound. Such pressures may range from 1 toabout 7 atmospheres.

To promote the oxylalkylation reaction, alkaline catalysts can be used,such as sodium metal, sodium hydride, sodium hydroxide, sodiummethoxide, sodium ethoxide, and the corresponding potassium compounds.The oxyalkylation reaction is conducted in the absence of water oralcohol or other substances which are themselves capable of reactingwith the oxyalkylating agent used.

VIII. Optional Additional Reactions

In some instances, an oxyalkylated partly blocked amine made asindicated above may be subjected to certain additional reactions beforebeing used. For example, in the case of producing modifying polymers foruse with a polyester resin such as the reaction product of ethyleneglycol and dimethyl terephthalate, it is desirable to have a modifyingpolymer which does not contain any free hydroxyl groups. Accordingly, insuch a case, it is desirable to block the reactive hydroxyl groups atthe ends of any oxyalkylene chain by reaction with a suitable cappingagent, such as monocarboxylic acid. Any suitable monocarboxylic acid maybe used, such as acetic acid, propionic acid, butyric acid, benzoicacid, toluic acid, capric acid, caprylic acid, myristic acid,cyclohexanecarboxylic acid, etc. Such a reaction with acid is conducted,of course, before the step of hydrolysis to regenerate amino groups,since otherwise the acid would react with such amino groups as well andthus destroy the usefulness of the modifying polymer.

It will also be apparent to those skilled in the art that theoxyalkylated blocked amines made in the manner described above are, ineffect, diols or polyols, depending upon the number ofhydroxyl-terminated oxyalkylene chains in the molecule. Such diols orpolyols are capable of reacting with difunctional or higher functionalcompounds such as diacids, diesters of diacids, diisocyanates, anddiepoxides to form linear or branched polymers.

Diisocyanates which may be used include the following:

2,4-toluene diisocyanate,

2,6-toluene diisocyanate,

mixtures of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate,

3,3-tolidene-4,4'-diisocyanate,

1,5-naphthalene diisocyanate,

xylylene diisocyanate,

1,2-phenylene diisocyanate,

chlorophenylene diisocyanate,

hexamethylene-1,6-diisocyanate,

bis(3-isocyanatopropyl) ethane,

bis(4-isocyanatophenyl) methane,

bis(3-methyl-4-isocyanatophenyl) methane,

tetramethylene-1,4-diisocyanate,

cyclohexane-1,4-diisocyanate,

1-methoxyphenyl-2,4-diisocyanate,

3,3'-dimethoxy-4,4'-biphenyl diisocyanate,

3,3'-dimethyl-4,4'-biphenyl diisocyanate,

3,3'-dimethyldiphenylmethane-4,4'-diisocyanate,

m-phenylene diisocyanate,

p-menthane-1,8-diisocyanate,

4,4'-dicyclohexyldiisocyanate,

1,5-pentamethylene diisocyanate,

isophorone diisocyanate,

trimethyl hexamethylene diisocyanate,

diphenylmethyl-4,4'-diisocyanate, and

4,4'-methylene-bis(cyclohexylisocyanate).

Dicarboxylic acids which may be used include the following:

azelaic acid,

glutaric acid,

pimelic acid,

succinic acid,

adipic acid,

sebacic acid,

2-methyl adipic acid,

diglycolic acid,

thiodiglycolic acid,

fumaric acid,

itaconic acid,

cyclohexane-1,3-dicarboxylic acid,

cyclopentane-1,4-dicarboxylic acid,

2,5-norbornanedicarboxylic acid,

phthalic acid,

isophthalic acid,

terephthalic acid,

t-butylisophthalic acid,

phenylenediacetic acid,

phenylenedipropionic acid,

2,6-naphthalenedicarboxylic acid,

1,4-naphthalenedicarboxylic acid,

1,5-naphthalenedicarboxylic acid,

1,7-naphthalenedicarboxylic acid,

4,4'-diphenic acid,

4,4'-sulphonyldibenzoic acid,

4,4'-oxydibenzoic acid,

binaphthyldicarboxylic acid,

4,4'-stilbenedicarboxylic acid, and

9,10-triptycenedicarboxylic acid. In appropriate circumstances themethyl esters may be used. Dimethyl terephthalate is an example.

Diepoxides which may be used include:

Bisphenol A diepoxide,

ethane diol diglycidyl ether,

1,4-butane diol diglycidyl ether,

diglycidyl ether having the formula: ##STR2## and diglycidyl ethers ofthe formula: ##STR3## wherein R' is the hydrocarbon residue of a diol##STR4## wherein R is a C₂ to C₄ alkylene and n is an integer from 1 toabout 350.

Preparation of diepoxides of the type just mentioned is described in thebook entitled Epoxy Resins by Lee and Neville, published by McGraw HillBook Company, New York (1957). Phenols which may be used to prepare thediglycidyl ethers include: ##STR5## where

n and m are integers from 1 to 10. Diols which may be used to preparethe diglycidyl ethers include: ethylene diol, 2,3-butanediol,1,6-hexanediol, etc. (e.g. alkylene and alkane diols having two to 12carbon atoms). Poly(alkylene ethers) which may be used to prepare thediglycidyl ethers include: polyethylene glycols, polypropylene glycolsand copolymers thereof, wherein the poly(alkylene ethers) have amolecular weight between about 106 and 10,000. The diglycidyl ether ofBisphenol A is a preferred diepoxide for use in carrying out theinvention, since it is inexpensive and commercially available.

Again, such reactions with diisocyanates, dicarboxylic acids, diesters,or diepoxides are to be conducted prior to the step of hydrolysis toregenerate amino groups. Mixtures of the foregoing kinds of difunctionaland higher functional materials may likewise be used in some instances.

IX. Hydrolysis to Regenerate Free Amino Groups

The oxyalkylated partly blocked amine, possibly further modified asdescribed in the preceding section, is hydrolyzed to form the modifyingpolymers of this invention. This results in a splitting of theoxyalkylated partly blocked amine at the point or points where thecarbonyl and the amino groups originally combined, without disturbingthe alkylene oxide units added during oxyalkylation. The hydrolysiseffects a regeneration of the carbonyl compound originally employed as ablocking agent. This step of hydrolysis to regenerate free amino groupsmay be conducted, as desired, either before the bringing together of themodifying polymer and the polymer to be modified, or after. Thehydrolysis reaction takes place spontaneously upon contacting themodifying polymer with water, even under ambient conditions oftemperature. However, heat may be employed.

X. Use of Modifying Polymer

The modifying polymer, in either its amine-blocked or amine-regeneratedform, must be brought into contact with the polymer substrate to bemodified. In some instances this may be done by incorporating it into amelt of the polymer substrate and uniformly dispersing it prior to theformation of sheets or fibers. In other instances, this may be done byapplying the modifying polymer to fibers, strands, sheets and the like.

Modifying polymers in their amine-regenerated form are quite reactivetowards polyesters, polyurethanes, and polyamides, especially atadvanced temperatures such as 100-300 degrees Centigrade, depending onthe substrate. In the case of modifying polymers in their amine-blockedform, the formation of the free amine takes place rather readily, asmentioned above, when water is permitted to react with the modifyingpolymer, which in some cases may take place at some subsequent step ofthe process after the modifier is blended with the substrate, such as awashing step. In either event, the free reactive primary amino group (orgroups) of the modifying polymer finds in the substrate a portion of itsstructure with which it (or they) may react by, for example, amidation(in the case of a polyester) or transamidation (in the case of apolyurethane or polyamide). Having thus become bonded covalently intothe substrate, the modifying polymer alters the properties of thesubstrate in a manner that is permanent and not destroyed by washing orlong continued use.

XI. Further Modifications or Uses

It is possible in accordance with this invention to provide a modifyingpolymer having two or more free primary amine groups. As an example,diethylenetriamine may be end-blocked with two moles of acetone and thenoxyalkylated. Modifying polymers that have two or more amine groups maybe used as diamines or polyamines are used in the art, namely, they maybe reacted with dicarboxylic acids to produce polyamides or withdiisocyanates to produce polyureas. Thus, it is possible to use such amodifying polymer as a partial replacement for a diamine that is beingso used to make such a polymeric material. Moreover, in some cases itmay be desirable to replace a diamine formerly used entirely with adiamine that comprises a modifying polymer according to this invention.

Still another use that may be made of a modifying polymer according tothe present invention is the possibility of producing, for example, anexternal anti-stat material by curing the modifying polymer with asuitable curing agent, such as a diepoxide. The free hydrogen atoms ofthe amino groups of a modifying polymer according to this invention mayin some circumstances be capable to being reacted with (cured by) adiepoxide to produce a polymer of high molecular weight which, becauseof the relatively hydrophilic nature of the modifying polymers of thisinvention, will be satisfactorily anti-static and at the same timecompatible with and adherent to a polymer to which such materials areapplied, whether sequentially or in admixture. This modification isillustrated below in Example 3.

The invention described above may be illustrated by the followingspecific examples, which are to be taken as illustrative and not in alimiting sense. In the examples, parts are by weight unless indicated tothe contrary.

EXAMPLE 1

A three-liter round-bottom flask was charged with 1000 grams ofdiethylene triamine and 200 grams of methyl isobutyl ketone. The flaskwas equipped with a mechanical stirrer, thermometer and thermometerwell, Dean-Stark trap with thermometer and condenser, one-literpressure-equalizing dropping funnel, and nitrogen-sweep means. Under aslow nitrogen sweep the reaction mixture was heated towards a refluxtemperature, while 800 grams of methyl isobutyl ketone were charged tothe dropping funnel. When the reactor temperature reached 80°Centigrade, slow addition of the methyl isobutyl ketone was begun. Afterone hour, the reactor temperature had reached 137° Centigrade, at whichpoint reflux was achieved. The refluxing vapor had an averagetemperature throughout the rest of the condensation reaction of between113° and 123° Centigrade. The slow, continuous addition of methylisobutyl ketone to the reactor was continued over a period of 4 hours,and the reaction mixture was thereafter maintained at reflux temperaturefor an additional hour, at which time further evolution of water ceased(190 grams of water collected, versus 181 grams theoretical).

The mixture was then vacuum-distilled at an absolute pressure of 10millimeters of mercury maximum and a temperature of 90° Centigrade forone-half hour to remove volatiles weighing 70 grams. The resultantreaction mixture was then employed in subsequent steps without furtherpurification.

An autoclave of about 3.8 liter capacity was charged with 556 grams ofthe above-mentioned ketimine (3 moles), and 575 grams of propylene oxide(a 10 percent excess) was added to the autoclave over a period of twohours at 100° Centigrade. The pressure in the autoclave was 5.7atmospheres. Thereafter, the autoclave was vented under nitrogen, and11.2 grams of potassium hydroxide of 95 percent purity was added. Theautoclave was sealed, and the contents were subjected to an absolutepressure of less than or equal to 10 millimeters of mercury for one hourat 125° Centigrade. During this treatment, 55 grams of volatile materialwere removed, which corresponds to a 10 percent excess of propyleneoxide (57.5 grams). The above-mentioned vacuum was relieved with theaddition of a second charge (1669 grams) of propylene oxide, whichcharge was added over a period of four hours. An additional two hourswere allowed for the reaction of this further addition of propyleneoxide. This yields a material that may be called an oxypropylatedketimine.

A 315-gram portion of the oxypropylated ketimine mentioned above wastreated with 1.5 grams of potassium hydroxide. The material was thensubjected to reduced pressure, to remove volatiles.

An autoclave of 3.8 liter capacity was charged with 315 grams of thematerial so treated, under a nitrogen blanket, and the autoclave wasthen sealed and evacuated to less than 10 millimeters of mercuryabsolute pressure, while being heated to a temperature of 115°Centigrade. The vacuum in the autoclave was relieved by the addition ofa further quantity of propylene oxide (1225 grams), over a period ofthree hours. Propylene oxide was allowed to react out for two hours(maximum pressure 7.05 atmospheres), and thereafter, the autoclave wasvented and was pressurized with nitrogen to 3.3 atmospheres. Ethyleneoxide (1260 grams) was then fed in, over 5.5 hours, and permitted toreact until a constant pressure was achieved. The mixture was cooled to80° Centigrade and discharged under a nitrogen blanket.

Thereafter, a two-liter three-necked round-bottom flask was equippedwith a mechanical stirrer, a thermometer, and a water-return trap andcondenser, and into such equipment there were charged 716 grams ofpolyol material made as described above, along with 100 grams ofdistilled water. The mixture was heated to a reflux temperature forabout two hours, during which time there was obtained as distillate anazeotrope of methylisobutyl ketone and water. An 81 percent yield ofmethyl isobutyl ketone (60.5 grams) was isolated, dried over magnesiumsulfate, and compared with a known sample of methylisobutyl ketone byinfra-red spectral analysis. Residual catalyst was neutralized by adding0.24 milliliters of phosphoric acid, and then the reaction mixture wassubjected to vacuum, to remove water. Analysis of titration, before andafter treatment with acetic anhydride, revealed 0.52 percent total aminenitrogen, versus 0.47 percent calculated, and 0.38 percent tertiarynitrogen, versus 0.31 percent calculated. This shows that the ketiminesurvives the oxyalkylation step.

There was thus prepared a polymeric material that was stable up to 320°Centigrade as determined by TGA in a nitrogen atmosphere, exhibited asink time for a 0.1 weight percent solution of 60 seconds, exhibited asa solution of 0.1 weight percent a surface tension of 32.8 dynes percentimeter, and a cloud point in a one weight percent aqueous solutionof 83° Centigrade. The pH of the one percent solution was 10.

EXAMPLE 2

This example shows the preparation of the bis-Schiff-base polyalkoxylateof triethylene tetramine.

A three-liter, four-necked flask was charged with 585 parts (4 moles) oftriethylene tetramine and 1000 parts (10 moles) of methyl isobutylketone. The flask was equipped with a mechanical stirrer, a thermometerand thermometer well, a Dean-Stark trap, and means for providing a slownitrogen sweep. The reaction mixture, a colorless and homogeneoussolution, was heated to reflux temperature. Azeotropic water removalstarted when the reactor reached 105° Centigrade. After 10.5 hours, 141parts of water had been collected (versus 144 parts theoretical).Further water formation had become imperceptibly slow, the reactor beingat 155° Centigrade and the refluxing vapor at 125° Centigrade. Thereaction was stopped by lowering the reactor temperature to 120°Centigrade. The reaction mixture was vacuum-distilled for one hour at 5millimeters of mercury absolute pressure, thereby removing 212 parts ofunreacted methyl isobutyl ketone. The product was a light-yellow mobileliquid, amounting by weight to a 96.4 percent yield of the diketimineresulting from the reaction of triethylene tetramine and methyl isobutylketone.

To a stirred autoclave of approximately 3.8 liters capacity there werecharged 617 parts (approximately 2 moles) of the diketimine mentionedabove. At 60° Centigrade under 3.3 atmospheres pressure, 211 parts(approximately 4.8 moles) of ethylene oxide were added continuously over100 minutes. The temperature was raised to 80° Centigrade for 2 hours.The reaction mixture was cooled to 60° Centigrade and discharged undernitrogen, giving 799 parts of product. A small sample wasvacuum-distilled at 60° Centigrade for one hour at 1 millimeter ofmercury absolute pressure to remove volatiles and then subjected toelemental analysis. Calculated for C₂₂ H₄₄ N₄ O₂ :66.62% C, 11.18% H,14.13% N Found: 66.8% C, 11.3% H, 13.9% N.

Further evidence of the structure was obtained by heating a small sampleof the product with water for one hour to hydrolyze the product andregenerate methyl isobutyl ketone. In this test, 87% of the calculatedquantity of methyl isobutyl ketone was isolated. Analysis by titrationbefore and after treatment with acetic anhydride revealed a total aminecontent of 20.6% and a tertiary-amine content of 10.9%, which agreeswith the theoretical values for C₂₂ H₄₄ N₄ O₂ when hydrolyzed to theextent indicated above.

A higher ethoxylate was prepared. To a one-liter, three-necked flaskequipped with a mechanical stirrer, a thermometer and thermometer well,and a vacuum distillation take-off assembly, there were charged 607parts of the diketimine diethanolamine, which was then heated andvacuum-distilled to remove volatiles (100° Centigrade, 15 minutes, 1 to3 millimeters of mercury). The vacuum was relieved with nitrogen, 14.5parts of sodium methoxide powder were quickly added, and the vacuum wasimmediately reestablished. In 45 minutes of additional vacuumdistillation under the same conditions, 12 parts of distillate werecollected. The vacuum was again relieved with nitrogen, and 585 parts ofthe catalyzed intermediate were transferred to an autoclave ofapproximately 3.8 liters capacity. The the autoclave there were alsocharged 1131 parts by weight of ethylene oxide over a period of threehours with the autoclave contents at 125° Centigrade. A sample, 334parts, was removed and treated with 70 milliliters of water at refluxfor 1 hour, and 53 parts of methyl isobutyl ketone were isolated (theorypredicts 57.4 parts, based upon theoretical further addition of about17.4 oxyethylene units). Titration, before and after treatment withacetic anhydride, indicated 5.26% total titratable amine (theory, 5.8%)and 2.82% tertiary amine (theory, 2.9%). This proves that the ketiminesurvives the oxyethylation step.

EXAMPLE 3

To a two-liter round-bottom flask equipped with a mechanical stirrer,thermometer, Dean-Stark trap, and condenser, there were charged 387grams of hexamethylene diamine, 193.5 grams of reagent-grade acetone,and 380 grams of reagent-grade toluene. The solution was heated to areflux temperature, which slowly increased from 87° Centigrade to 127°Centigrade over a period of 5.5 hours. During this interval, 62 grams ofwater-acetone azeotrope were collected (theoretical, 60 grams). Thereaction mixture was subjected to vacuum distillation (40° Centigrade,1.5 millimeters of mercury absolute pressure) to remove the toluene. Thevacuum distillation was continued, with the collection of a firstfraction weighing 316 grams at temperatures between 79 and 100°Centigrade and absolute pressures of 1.5 to 2.0 millimeters of mercury,and with a second fraction weighing 150 grams being collected attemperatures between 100° Centigrade and 115° Centigrade. There remaineda pot residue weighing 25 grams.

For further processing, there was prepared a mixture of all of the firstfraction mentioned above and 28 grams of the second fraction. A quantity(340 grams) of this mixture was charged to an autoclave of 3.8-litercapacity, which was then purged with nitrogen and pressurized withnitrogen to 3.3 atmospheres. An initial charge of 324 grams of ethyleneoxide was then begun, and it was observed that an exothermic reactionwas taking place. The temperature of the reaction mixture was maintainedat 100° Centigrade by continuing the addition of ethylene oxide. Thereaction mixture was permitted to come to a constant pressure, andthereafter the reaction mixture was stripped of its volatile content ata maximum absolute pressure obtained of 10 millimeters of mercury, thequantity of volatiles being trapped in this way amounting to 9.9 grams.Potassium hydroxide (1.0 gram) was then added, and the reaction mixturewas stripped by being subjected for one hour at a temperature of 130°Centigrade to an absolute pressure of less than 10 millimeters ofmercury. Thereafter, the vacuum was released with nitrogen, and theautoclave was pressurized to 3.3 atmospheres with nitrogen, and a secondcharge of ethylene oxide, amounting to 470 grams, was added to thereaction mixture in the autoclave over a period of two hours at atemperature of 130° Centigrade. The reaction mixture was permitted tocome to a constant pressure, and thereafter, the autoclave was vented,and there was withdrawn from it a viscous, tan-colored liquid.

A portion of the viscous, tan-colored liquid was then heated with anexcess of water to reflux temperature, then subjected to vacuumdistillation to recover the free amine. Analysis by titration, beforeand after treatment with acetic anhydride, revealed 6.2 percent totaltitratable nitrogen (5.8 percent, calculated) and 4.5 percent oftertiary nitrogen (2.9 percent, calculated). As before, this indicatesthat the ketimine survives the oxyalkylation step.

To a one-liter round-bottom flask equipped with a short-pathdistillation take-off, a mechanical stirrer, and a thermometer, therewere charged 337 grams of the above-mentioned viscous tan-coloredliquid, and 0.1 gram of sodium methoxide powder. This mixture wassubjected to vacuum for one-half hour while the temperature thereof wasraised to 120° Centigrade. The vacuum was intermittently relieved withnitrogen, and small charges of dimethyl terephthalate (5 to 10 grams)were added. Vacuum was reestablished, and methanol was removed.

When the mixture appeared to be very thick, the temperature of thereaction mixture was raised to 140° Centigrade, and the addition ofdimethyl terephthalate was continued. When a total of 103.5 grams ofdimethyl terephthalate had been added, the reaction was stopped by theaddition of 0.2 milliliters of phosphoric acid. There was thus obtaineda polyester which was extremely viscous at room temperature but had aviscosity of 7400 centipoises at 100° Centigrade. This material will bedesignated "Agent X" hereinbelow.

To a 100-gram aqueous solution containing 10 weight percent of aceticacid, there were added 35 grams of Agent X. This was divided into fourparts. To one part, nothing further was added. To a second part, therewere added 0.35 gram of accelerator EN (EPONITE 100 diepoxide) and 0.17grams of zinc fluoborate. To a third portion, there were added 1.75grams of accelerator EN and 0.87 gram of zinc fluoborate, and to thefourth portion there were added 3.5 grams of accelerator EN and 1.75grams of zinc fluoborate. The portions were formed into films and driedat 100° Centigrade for one hour and then for 10 minutes at 150°Centigrade. The films that were obtained with the untreated control andwith the portion to which 0.35 gram of accelerator EN was added werevery tacky; the portion to which 1.75 grams of accelerator EN was addedwas slightly tacky, and the portion containing 3.5 grams of acceleratorEN was non-tacky and definitely cured.

For testing upon nylon fiber, there was prepared a mixture correspondingin composition to the fourth portion mentioned above, i.e., theabove-mentioned polyester, dissolved in acetic acid, with appropriatequantities of accelerator EN and zinc fluoborate added to it. Thiscomposition was applied to nylon fiber at a rate of 7 to 13.9 weightpercent. For purposes of comparison, a similar portion of nylon fiberwas treated at the same rate with a known commercial antistatic agent.

Resistivity tests were conducted, not only on the nylon as initiallytreated but also upon the nylon after repeated washing in a"Terg-O-Meter" machine (20 minutes, 100 revolutions per minute, 60°Centigrade). The results of this testing are presented below in TableNo. I. In the results presented below, the "Log R" represents thelogarithm to the base 10 of the resistance in ohms per square; a highvalue of "Log R" indicates that the fiber is relatively hydrophobic andis consequently likely to develop or hold a static-electricity charge.

                  Table I                                                         ______________________________________                                        Material       No. Washings   Log R                                           ______________________________________                                        Untreated Control                                                                            1              14.5                                            "              5              14.6                                            "              7              14.6                                            "              10             14.4                                            Nylon treated with                                                                           1              10.7                                            known commercial                                                              antistatic agent                                                                             2              10.7                                            "              3              11.9                                            "              5              11.5                                            "              7              12.9                                            "              10             13.9                                            Nylon treated with                                                                           1              11.3                                            13.9 weight per-                                                              cent of Agent X                                                                              2              11.5                                            "              3              11.3                                            "              5              11.7                                            "              7              11.3                                            "              10             12.1                                            Nylon treated with                                                                           1              11.7                                            10.4 weight per-                                                              cent of Agent X                                                                              2              11.7                                            "              3              11.6                                            "              5              12.0                                            "              7              11.9                                            "              10             12.2                                            Nylon treated with                                                                           1              12.4                                            7.0 weight per-                                                               cent of Agent X                                                                              2              12.5                                            "              3               12.3                                           "              5              12.5                                            "              7              12.5                                            "              10             12.6                                            ______________________________________                                    

The foregoing data show that Agent X is an effective antistatic agent,reducing the resistivity to about one percent or less of the value foran untreated control. Moreover, in comparison with the known commercialantistatic agent, Agent X was initially slightly less effective, but itwas remarkably superior in regard to retaining its effect throughrepeated washings.

EXAMPLE 4

To a two-liter three-necked round-bottom flask equipped withthermometer, mechanical stirrer, and Dean-Stark trap, there were charged428 grams of diethylene triamine and 1200 grams of methyl isobutylketone. The mixture was heated to reflux under a slow nitrogen sweep.Refluxing began at 110° Centigrade and was continued for seven hours,finishing at the boiling point of methyl isobutyl ketone. Azeotropicremoval of water accounts for 94 percent of the water theoreticallypresent. Excess methyl isobutyl ketone was removed under reducedpressure. the intermediate product thus remaining was employed in thenext step without further purification.

An autoclave of 3.8 liters capacity was charged with 534 grams of theabove-mentioned intermediate product. The charge was swept withnitrogen; then the autoclave was sealed, pressurized with nitrogen to3.3 atmospheres, and heated to 70° Centigrade. Then, over a period oftwo hours, ethylene oxide (150 grams) was added. (This was a 62-gramexcess of ethylene oxide, which was lost when the autoclave was latervented.)

The autoclave was vented to atmospheric pressure, and 3 grams of 95percent flake potassium hydroxide were added. The autoclave was resealedand evacuated to an absolute pressure of 10 millimeters of mercury orlower. The reaction mixture was stripped at 125° Centigrade for onehour. Nitrogen was admitted to the autoclave to relieve the vacuum andcreate a pressure of 3.3 atmospheres. Then over four hours, 1451 gramsof ethylene oxide were added. The contents of the autoclave were cooledto 80° Centigrade and discharged.

To a two-liter, three-necked round-bottom flask equipped with mechanicalstirrer, thermometer and water-return trap there were charged 894 gramsof the above-mentioned autoclave contents and 100 milliliters of water.After 1 hour of refluxing, removal of methyl isobutyl ketone ceased.There were isolated 150 grams of methyl isobutyl ketone, an 83 percentyield. The mixture remaining was vacuum-stripped (100° Centigrade, onehour, absolute pressure 10 millimeters of mercury maximum). To themixture there was then added a six weight percent portion of finelydivided activated silicate material to adsorb the basic catalystpresent. Filtration and vacuum stripping completed the preparation..

A sample of the material so produced was titrated, before and aftertreatment with acetic anhydride, to determine total and tertiary aminenitrogen.. The titrations showed 5.8 percent total nitrogen (5.3percent, calculated) and 2.4 percent tertiary nitrogen (3.6 percent,calculated). These results show that the ketimine survived theoxyalkylation step.

The material so produced is an example of a modifying polymer accordingto the invention. It may be used in various ways, such as by adding 3weight percent of it to a melt of a polyester resulting from thereaction of ethylene glycol and dimethyl terephthalate.

EXAMPLE 5

One mole of methyl isobutyl ketone is reacted with one mole of a mixtureof 2,4- and 2,6-diaminotoluenes, and the resulting ketimine is reactedwith 30 moles of ethylene oxide. The resulting material is added, to theextent of 5 weight percent, to a melt of Nylon 6-6 (polyhexamethyleneadipamide). The melt is spun into fibers, which are then heated to 100°Centigrade in a water-washing step, in which a hydrolysis occurs,regenerating the amine groups and thus causing the modifying polymer toreact with the Nylon 6-6.

EXAMPLE 6

One mole of diethylene triamine is reacted first with 2 moles of2-ethylhexaldehyde, then with 10 moles of propylene oxide, then with 30moles of ethylene oxide, then with 10 moles of propylene oxide. Theresulting product is then hydrolyzed to restore its free amino groups,yielding a material which is used in making a modified Nylon 6-6 bybeing substituted for approximately 10 percent of the hexamethylenediamine ordinarily used.

EXAMPLE 7

An amine-terminated polymer of relatively low molecular weight is madeby reacting a quantity of hexamethylene diamine with a relatively smallproportion of adipic acid. Such polymer is reacted with diethylketone toblock some of its amino groups, and then with ethylene oxide to obtain amaterial of desired viscosity. The material is then hydrolyzed torestore its free amino groups and added, at 7 weight percent, to a meltof Nylon 6 (polyepsiloncaprolactam).

EXAMPLE 8

One mole of ethylene diamine is reacted with one mole of diethyl ketone,and the resulting ketimine is reacted with 20 moles of ethylene oxide toform a diol, which is then reacted with dimethyl terephthalate to form apolyester of relatively low molecular weight. The polyester is dissolvedin a suitable solvent such as toluene and sprayed upon freshly formedpolyester fiber, which is then heated in an oven with a moist atmosphereto cause hydrolysis and amide formation.

EXAMPLE 9

One mole of 2,4-diaminotoluene is reacted with one mole of methylisobutyl ketone, and then with 15 moles of ethylene oxide to form adiol. The diol is substituted for 5 weight percent of ahydroxyl-terminated prepolymer ordinarily used with toluene diisocyanateto make a polyurethane resin in accordance with a typical foamingformulation which, during foaming, produces water and heat. A modified,moe hydrophilic polyurethane foam is obtained.

EXAMPLE 10

One mole of tetraethylene pentamine is reacted with two moles ofisobutyraldehyde to form a blocked amine. The blocked amine is reactedwith 90 moles of ethylene oxide, and then hydrolyzed and dissolved inmixed xylenes and applied to fibers of Nylon 6-6 after they have beenspun and woven. The treated cloth is then heated to about 150°Centigrade to cause reaction of the nylon and the modifying polymer soapplied.

EXAMPLE 11

One mole of 2,4-diaminotoluene is reacted with one mole of methylisobutyl ketone, and then with 15 moles of ethylene oxide to form adiol. The diol is added to a melt of a polyurea resulting from thereaction of hexamethylene diisocyanate with a 90:10 mixture ofhexamethylene diamine and isophorone diamine, the diol being added tothe extent of 5 weight percent of the melt. Subsequent hydrolysis yieldsa hydrophilized polyurea composition.

I claim:
 1. A method of providing fibers selected from the groupconsisting of polyamides, polyesters, and polyurethanes with a durableanti-stat coating which comprisespreparing a first polymer having (a) anoxyalkylene content of 20 to 95 weight percent and sufficient to renderit hydrophilic and (b) a blocked pendant amino group, said first polymerbeing difunctional, chain-extending said first polymer by reaction witha difunctional compound selected from the group consisting of diacids,diesters of diacids, diisocyanates and diepoxides to form achain-extended polymer containing plural blocked-amine functionalgroups, hydrolyzing said chain-extended polymer to obtain a polymercontaining a plurality of reactive amino groups, curing the polymer soobtained by reaction with a quantity of a diepoxide effective to producean anit-stat agent in the form of a non-tacky, definitely cured film,and applying said anti-stat agent to said fibers.
 2. A method as definedin claim 1, wherein said fibers are of nylon.
 3. A method as defined inclaim 2, wherein said first polymer is prepared by reacting alower-alkyl carbonyl compound with a lower aliphatic diamine to obtain aketimine containing a reactive hydrogen atom, then oxyalkylating saidketimine.
 4. A method as defined in claim 3, wherein said lower-alkylcarbonyl compound is acetone and said lower aliphatic diamine ishexamethylene diamine, and dimethyl terephthalate is used as adifunctional compound for chain-extending said first polymer.